Sustained release pharmaceutical composition

Abstract

Sustained release pharmaceutical composition consisting of a hard gelatine capsule containing film coated spheroids, the spheroids comprising propranolol, or a pharmaceutically-acceptable salt thereof, in admixture with non-water-swellable microcrystalline cellulose, and the said spheroids having a film coat comprising ethylcellulose optionally together with hydroxypropyl methylcellulose and/or a plasticizer.

What we claim is: 
     
       1. A sustained release pharmaceutical composition consisting of a hard gelatine capsule containing film coated spheroids, the said spheroids comprising, prior to coating, 40 to 65% by weight of propranolol, or a pharmaceutically-acceptable acid-addition salt thereof, in admixture with non-water-swellable microcrystalline cellulose, and the said spheroids having a film coat comprising ethylcellulose or ethycellulose and hydroxpropyl methylcellulose. 
     
     
       2. The composition claimed in claim 1 in which the uncoated spheroids contain 50 to 60% by weight of propranolol hydrochloride and 50 to 40% by weight of non-water-swellable microcrystalline cellulose, respectively. 
     
     
       3. The composition claimed in claim 1 in which the film coat comprises 5 to 15% by weight of the coated spheroids. 
     
     
       4. The composition claimed in claim 1 in which the ethylcellulose has a viscosity of 50 cps at 20° C. 
     
     
       5. The composition claimed in claim 1 in which the hydroxypropyl methylcellulose has a viscosity of 6 cps at 20° C. 
     
     
       6. The composition claimed in claim 1 in which the film coat comprises 80 to 100% by weight of ethylcellulose and 20 to 0% by weight of hydroxypropyl methylcellulose. 
     
     
       7. The composition claimed in claim 1 in which the film coat contains up to 20% by weight of a plasticizer. 
     
     
       8. The composition claimed in claim 1 which contains 100 to 200 mg. of propranolol or a pharmaceutically-acceptable acid-addition salt thereof. 
     
     
       9. The composition claimed in claim 1 in which, prior to coating, the spheroids contain 60% by weight of propranolol hydrochloride in admixture with 40% by weight of non-water-swellable microcrystalline cellulose, and the spheroids have a film coat consisting of 90% by weight of ethylcellulose having a viscosity of 50 cps at 20° C. and 10% by weight of hydroxypropyl methylcellulose having a viscosity of 6 cps at 20° C., the film coat comprising 9 to 10% by weight of the coated spheroids, and the said composition containing 160 mg. of propranolol hydrochloride.